`ngrok list`: List tunnel names from config file

src/ngrok/client/cli.go

@@ -22,6 +22,7 @@ Examples:
 Advanced usage: ngrok [OPTIONS] <command> [command args] [...]
 Commands:
 	ngrok start [tunnel] [...]    Start tunnels by name from config file
+	ngrok list                    List tunnel names from config file
 	ngrok help                    Print help
 	ngrok version                 Print ngrok version
 
@@ -100,6 +101,8 @@ func ParseArgs() (opts *Options, err error) {
 	}
 
 	switch opts.command {
+	case "list":
+		opts.args = flag.Args()[1:]
 	case "start":
 		opts.args = flag.Args()[1:]
 	case "version":

src/ngrok/client/config.go

@@ -160,6 +160,13 @@ func LoadConfiguration(opts *Options) (config *Configuration, err error) {
 			}
 		}
 
+	// list tunnels
+	case "list":
+		for name, _ := range config.Tunnels {
+			fmt.Println(name)
+		}
+		os.Exit(0)
+
 	// start tunnels
 	case "start":
 		if len(opts.args) == 0 {